Akytec SMI2-M User manual

akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany · Tel.: [phone] · www.akytec.de
SMI2-M
RS485 Multi-Color Display
User guide
SMI2-M_2022_0001_EN
© All rights reserved
Subject to technical changes and misprints

akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany · Tel.: [phone] · www.akytec.de
1
Contents
1. Introduction.....................................................................................................................................................2
1.1 Terms and abbreviations .........................................................................................................................2
1.2 Symbols and key words...........................................................................................................................2
1.3 Intended use ............................................................................................................................................2
1.4 Limitation of liability..................................................................................................................................2
1.5 Safety.......................................................................................................................................................2
2. Overview..........................................................................................................................................................4
2.1 Basic features ..........................................................................................................................................4
2.2 Design......................................................................................................................................................4
3. Specifications .................................................................................................................................................6
3.1 Operating conditions................................................................................................................................6
4. Configuration ..................................................................................................................................................7
4.1 Connection to akYtecToolPro..................................................................................................................7
4.2 RS485 interface .......................................................................................................................................7
4.3 Modbus common .....................................................................................................................................8
4.3.1 Safe state.............................................................................................................................................9
4.4 Modbus Slave ..........................................................................................................................................9
4.5 Modbus Master ........................................................................................................................................9
4.6 Modbus Spy...........................................................................................................................................10
4.7 Device settings ......................................................................................................................................11
4.7.1 Display ...............................................................................................................................................12
4.7.2 Displayed value..................................................................................................................................13
4.7.3 Extended control ................................................................................................................................14
4.8 Device status and errors........................................................................................................................17
4.9 Password ...............................................................................................................................................18
5. Installation.....................................................................................................................................................19
5.1 Mounting ................................................................................................................................................19
5.2 Wiring.....................................................................................................................................................20
5.3 RS485 network ......................................................................................................................................20
6. Factory settings restoration........................................................................................................................22
7. Maintenance..................................................................................................................................................23
8. Transportation and storage.........................................................................................................................24
9. Scope of delivery..........................................................................................................................................25
Appendix A. Galvanic isolation........................................................................................................................26
Appendix B. Modbus application.....................................................................................................................27

Introduction
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany · Tel.: [phone] · www.akytec.de
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1. Introduction
1.1 Terms and abbreviations
akYtecToolPro – configuration software
Modbus – application layer messaging protocol for client/server communication between devices
connected on different types of buses or networks, originally published by Modicon (now
Schneider Electric), currently supported by an independent organization Modbus-IDA
(https://modbus.org/)
TTL – transistor–transistor logic
1.2 Symbols and key words
WARNING
WARNING indicates a potentially dangerous situation that could result in death or serious inju-
ries.
CAUTION
CAUTION indicates a potentially dangerous situation that could result in
minor injuries
.
NOTICE
NOTICE indicates a potentially dangerous situation that could result in damage to property.
NOTE
NOTE indicates helpful tips and recommendations, as well as information for efficient and trou-
ble-free operation.
1.3 Intended use
The device has been designed and built solely for the intended use described here, and may only be used
accordingly. The technical specifications contained in this document must be observed.
The device may be operated only in properly installed condition.
Improper use
Any other use is considered improper. Especially to note:
– The device may not be used for medical appliances applied to maintain human life or health, its con-
trol or other effect on them.
– The device may not be used in explosive environment.
– The device may not be used in atmosphere in which there are chemically active substances.
1.4 Limitation of liability
Our company does not bear any responsibility with respect to breakdowns or damages caused by using the
product in a manner other than described in the Manual or in violation of the current regulations and tech-
nical standards.
1.5 Safety
WARNING
Ensure the mains voltage matches the voltage marked on the nameplate.
Ensure the device is provided with its own power supply line and electric fuse.

Introduction
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany · Tel.: [phone] · www.akytec.de
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CAUTION
De-energize the equipment before servicing. Switch on the power supply only when all
works on the device are completed.
NOTICE
Supply voltage may not exceed 48 V. Higher voltage can damage the device.
If the supply voltage is lower than 10 V DC, the device cannot operate properly but will
not be damaged.
NOTICE
If the device is brought from a cold to a warm environment, condensation may form in-
side the device. To avoid damage to the device, keep the device in the warm environment
for at least 1 hour before powering on.

Overview
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany · Tel.: [phone] · www.akytec.de
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2. Overview
SMI2-M is a universally applicable LED display that receives data from a network over RS485 interface using
Modbus RTU / ASCII protocols and can be operated in slave, master or spy mode.
For details on Modbus working see Appendix B.
For Modbus protocol specifications see Modbus specifications.
The device can be configured with the configuration software akYtecToolPro (free) over USB (Sect. 4). The
software is available for download on akYtec.de.
2.1 Basic features
– Slave mode: receiving data from Master
– Master mode: querying data from Slave
– Spy mode: listening-in to data requested by the Master from another Slave
– Displaying received data according to display settings
– Extended display control
– Display safe state (Sect. 4.3.1)
– Error indication if no master activity or variable cannot be displayed
– Configuration with the akYtecToolPro software over USB interface
– Modification of configuration parameters over Modbus network
2.2 Design
1 - Micro-USB programming interface
2 - service button
3 - two plug positions of terminal block
Fig. 2.1External design

Overview
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Fig. 2.2Hardware block diagram
RS485-TTL converter - converts RS485 network signals into TTL signals used by the microcontroller.
Microcontroller - processes the data received over RS485 network.
Digital display - displays the variable received over RS485 network and error / alarm messages.
VS - secondary voltage source with galvanic isolation hat provides stable power supply and protection
against polarity reversal.
NOTE
When the device is powered from USB, the display brightness is by 50% reduced com-
pared to 24 V power supply.

Specifications
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3. Specifications
Table 3.1 General specification
Parameter
Value
Power supply
24 (10…48) V DC
Power consumption, max.
1.6 W
Display
4 digits with sign, 7 segments
Colors
green, yellow, red
Character height
14 mm
Network interface
RS485
Protocol
Modbus RTU, Modbus ASCII
Mode
Master, Slave, Spy
Baud rate
2.4…115.2 kbit/s
Galvanic isolation to power supply
500 V / 1 min.
Configuration interface
USB2.0 (Micro-USB)
Configuration software
akYtecToolPro
Flash memory write cycles, min.
10000
Enclosure
panel mounting in Ø22.5 mm borehole
Dimensions
48 x 26 x 65 mm
IP Code
front IP65, rear IP20
Application class
III (according to IEC 61140)
Weight
approx. 30 g
3.1 Operating conditions
The device is designed for natural convection cooling. It should be considered when choosing the installation
site.
The following environment conditions must be observed:
−clean, dry and controlled environment, low dust level
−closed non-hazardous areas, free of corrosive or flammable gases
Table 3.2 Operating conditions
Condition Permissible range
Ambient temperature -40…+70°C
Transportation and storage -40…+70°C
Relative humidity up to 80 % (at +25°C, non-condensing)
Altitude
up to 2000 m ASL
Vibration / shock resistance conforms to IEC 61131-2
EMC emission / immunity conforms to IEC 61131-2

Configuration
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4. Configuration
The device parameters can be set with akYtecToolPro or in the Slave mode by commands from a network
Master.
The complete parameter list is presented in Appendix B. You can also read it out from the device using the
toolbar item Parameter list in akYtecToolPro.
Parameter groups:
−RS485 interface (Sect. 4.2)
−Device settings (Sect. 4.7)
oModbus Master (Sect. 4.5)
oModbus Spy (Sect. 4.6)
oModbus common (Sect. 4.3)
oDisplay (Sect. 4.7.1)
oDisplayed value (Sect. 4.7.2)
oExtended control (Sect. 4.7.3)
−Device status (Sect. 4.8)
Configuration order:
−Establish connection to the akYtecToolPro software (Sect. 4.1)
−Select the operation mode (Slave, Master or Spy) in the parameter Device settings > Operation
mode
−Set the common communication parameters: in the groups RS485 interface and Modbus common
−Set the parameters of the selected mode
−Set the display parameters
4.1 Connection to akYtecToolPro
The connection to akYtecToolPro software running on the PC can be established over the Micro-USB inter-
face. The main power supply is not required.
To configure the device:
– Connect the Micro-USB programming connector on the device (Fig. 2.1. Pos. 1) to PC over a USB-
to-Micro-USB connection cable (not included).
– Start akYtecToolPro.
– In a new project, click the toolbar item Add devices .
– In the open dialog, select the interface STMicroelectronics Virtual COM Port.
– Select the protocol akYtec Autodetection Protocol.
– Select Find device and click Search (device address is 1 and cannot be changed).
– If the correct device is found, select it and click the button Add devices to add the device to the pro-
ject.
– If the device is password protected, enter the correct password.
If you forgot the password, restore the factory settings (Sect. 4.9, 6).
4.2 RS485 interface
The parameters in this group define the physical layer of data exchange over the RS485 port for all operating
modes.

Configuration
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Table 4.1 RS485 interface
Parameter Description Range
Default
value Access
Baud rate
Data transfer speed in bits per second
2400…115200
9600
RW
Data bits
Length of frames sent over Modbus network
8
8
RW
Stop bits
Number of stop bits
1 / 2
1
RW
Parity Error detection
none /
even /
odd
none RW
Silent interval
IDLE frame
- message frames are separated by
a silent interval of at least 1-character time.
t3.5 - message frames are separated by a silent
interval of at least 3.5-character time (Modbus
standard).
IDLE frame
/ t3.5
IDLE
frame RW
4.3 Modbus common
Open the node Device settings > Modbus common.
The parameter Address in Slave mode in this node is relevant only for the Slave mode. Other parameters
are common for all modes.
Table 4.2 Modbus common
Parameter Description Range
Default
value
Access
Address in Slave
mode
Device address in the Slave mode 1...255 1 RW
Byte order Inverse byte / register order of the re-
ceived variable (Example 1)
Unchanged /
Swap bytes /
Swap registers /
Swap bytes and
registers
Unchanged RW
Safe state timeout
Safe state activation delay after inter-
ruption of data transmission
0…60 s 0 RW
Safe state display
bitmask
Image displayed in the safe state (HEX
input)
0…FFFFFFFF 70404046 RW
Safe state color Display color in the safe state
Green /
Red /
Yellow
Green RW
Safe state blinking
Display blinking in the safe state
On / Off
Off
RW
Example 1: Parameter Byte order
Initial byte order
Parameter value
Final byte order
0xAABBCCDD
Unchanged
0xAABBCCDD
0xAABBCCDD
Swap bytes
0xBBAADDCC
0xAABBCCDD
Swap registers
0xCCDDAABB
0xAABBCCDD
Swap bytes and registers
0xDDCCBBAA

Configuration
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4.3.1 Safe state
Safe state is a state of the display after communication interruption, activated with the time delay (Safe state
timeout, Tab. 4.2). In the safe state, a variable of type IMAGE (Safe state display bitmask, Tab. 4.2) is
displayed.
If Safe state timeout is set to 0, the device does not enter the safe state and displays the last received val-
ue.
After power-on, the device is in the safe state until a valid request is received.
4.4 Modbus Slave
Set the parameter Device settings > Operation mode to SLAVE (Tab. 4.5).
In the Slave mode, the device receives data from the Master. The exchange protocol (Modbus RTU or Mod-
bus ASCII) is detected automatically.
The parameter Modbus common > Address in Slave mode defines the device address (Tab. 4.2).
NOTE
Saving of configuration parameters to flash memory
– The configuration parameters are all writable parameters, except those in the node Dis-
played value.
– The number of flash memory write cycles is limited (≥10000 cycles). Therefore, frequent
(cyclic) saving of configuration parameters is not recommended.
– If the new configuration parameters are not written to the flash memory, they will be lost
after turning off the device. After powering on, the device will start with the parameter values
previously stored in the flash memory.
– In case of configuration over Micro-USB interface, the configuration parameters are saved to
the flash memory.
– In case of configuration over RS485 interface, the configuration parameters are not automat-
ically saved to the flash memory. If it is necessary, the user has to do it manually, calling the
command Save-to-Flash Trigger (Tab. 4.5). The command is a single pulse , that triggers
on rising edge the saving of the configuration parameters to the flash memory.
– During the recording of configuration parameters, the brightness of the display decreases by
50% and the response time of the device increases for a short time up to 200 ms. This
should be considered when setting the timeout in the Master device.
– To estimate the remaining number of write cycles in %, use the parameter Device status >
Remaining flash write cycles (Tab. 4.10).
4.5 Modbus Master
Set the parameter Device settings > Operation mode to MASTER (Tab. 4.5).
In the Master mode, only one Slave device can be connected. The Master device sends requests with a
reading function to the Slave at a certain frequency. After each request, the Master waits for response from
the Slave for a predetermined time interval (Response timeout, Tab. 4.3). The received variable will be
displayed.
If no response is received within the response timeout, the Master sends the next request and starts the
Safe state timeout countdown (Tab. 4.2). If there is no response from the Slave during Safe state timeout,
the Master switches to the safe state (Sect. 4.3.1).